Russian intermediate range ballistic missile. The G-4 was designed by the Groettrup German team in the Soviet Union in competition with Korolev's R-3. Rocket chief Ustinov informed Groettrup of the requirement on 9 April 1949: to deliver a 3000 kg atomic bomb to a 3000 km. This requirement meant a massive improvement over existing V-2 technology. The G-4 was evaluated against Korolev's R-3 on 7 December 1949 - and the G-4 was found to be superior. Neither ended up in production, but the design concepts of the G-4 led directly to Korolev's R-7 ICBM (essentially a cluster of G-4's or R-3A's) and the N1 superbooster. Work on the G-4 continued through 1952.

The G-4 was designed by the Groettrup German team in the Soviet Union in competition with Korolev's R-3. Rocket chief Ustinov informed Groettrup of the new requirement on 9 April 1949. The specification was to deliver the first Soviet atomic bomb - total mass 3000 kg - to a 3000 km range - anywhere in Western Europe. This requirement meant a massive improvement over existing V-2 technology. A wide range of technical solutions were considered. These included use of 3 G-1's in a parallel-staging 'bundle' (or 'packet' as the Russians would later term it); winged missiles along the lines of the wartime A9/A10 or Saenger Antipodal Bomber (the G-3); or sequential stages, as used on the earlier G-1 and G-2 designs. Consideration was even given of using balloon tanks of high quality steel (as would be adopted in the USA for the Atlas ICBM). But the Russians did not have such alloys available, and the Germans kept the idea to themselves, 'in reserve'.

Groettrup's team finished the 20 volume design study in June 1949, three months after go-ahead. The selected configuration was a cylindrical single-stage design, which was aerodynamically stable in all flight regimes. As in previous designs, the liquid oxygen tank was switched to the forward position in comparison with the V-2, eliminating instrument and engine pre-cooling problems. The warhead was contained in a 1.40 m diameter cylinder, and the re-entry vehicle used the sharp-nosed 'fast point' preferred by the Soviet engineers. The Germans preferred the 'slow point' design - a blunt nose and conical sides - but the Russians feared a slow-falling warhead could be intercepted and felt the thermal problems of the sharp point could be solved.

The R-14 would use a new design high pressure cylindrical combustion chamber. This would feed a spherical mixing chamber. The German engineers worked with Glushko to build a subscale 7 tonne thrust, 60 atmosphere chamber pressure test model. Given the Russian designation ED-140, this was run 100 times between the summer of 1949 and April of 1950. 19 of these chambers would feed the chamber of the Glushko RD-110 engine slated for use in Korolev's competing R-3 rocket.

Unknown to the German team, their approach was evaluated against Korolev's R-3 on 7 December 1949 - and their design was found to be superior. Neither ended up in production, but the design concepts of the G-4 led directly to Korolev's R-7 ICBM (essentially a cluster of G-4's or R-3A's) and the N1 superbooster. Notable unique features of these rockets borrowed from the G-4 work included conical rocket body forms, 'sharp point' warheads or payload shrouds, forward positioning of the oxygen tanks, and elimination of aerodynamic surfaces.

The G-4 was the last design project worked on by the team. The G-4 was designated as the R-10 in the original secret Russian numbering scheme; and known to the Russians as the R-14 (the same designation given to the 3000 km range single stage IRBM finally delivered by Yangel to the Soviet armed forces in 1962).

Early Russian Ballistic Missiles The true configuration of the world's first ICBM, the R-7, was revealed only in 1967, ten years after its first test. The Soviet N1 moon rocket was only revealed in 1990, 21 years after its first launch. At the same time, other Russian ballistic missiles were routinely paraded before the cameras of the world press even before they went into service. The extraordinary sensitivity of the Soviet leadership over these Korolev designs may be traced to the fact that they derived from the work of the Groettrup German rocket engineering team. More...

Russo-German advanced rocket engine tests. - .
Nation: USSR. Related Persons: Glushko. The planned IRBM's (R-3 or G-4) would use a new design high pressure cylindrical combustion chamber. This would feed a spherical mixing chamber. The German engineers worked with Glushko to build a subscale 7 tonne thrust, 60 atmosphere chamber pressure test model. Given the Russian designation ED-140, this was run 100 times between the summer of 1949 and April of 1950. 19 of these chambers would feed the chamber of the Glushko RD-110 engine slated for use in Korolev's competing R-3 rocket.

Groettrup G-4 IRBM evaluated against Korolev's R-3. R-3 project reformulated - .
Nation: USSR. Related Persons: Korolev. Program: Navaho. The NTS (Scientific-Technical Soviet) of NII-88 met in plenary session and subjected Korolev's proposal to withering criticism. The G-4 was found to be superior. After heated discussion, the Soviet approved further development of technology for the R-3, but not the missile itself. The decisions were: an R-3A technology demonstrator would be built and flown under Project N-1 (probably to prove G-4 concepts). Under Project N-2 both the RD-110 and D-2 engines would proceed into development test in order to prove Lox/Kerosene propellant technology. Packet rocket and lightweight structure research for use in an ICBM would continue under project N-3 / T-1. Winged intercontinental cruise missile studies would continue under project N-3 / T-2. Neither the G-4 or R-3 ended up in production, but the design concepts of the G-4 led directly to Korolev's R-7 ICBM (essentially a cluster of G-4's or R-3A's) and the N1 superbooster. Work on the G-4 continued through 1952.